This reverts commit 793423cf07e51e3185b8680167115813589c057d.
The 64-bit alignment affects the size of efi_config_table_32_t,
which is used as an array type. On the other hand, the former
byte alignment could trigger alignment faults during firmware
calls on 32-bit ARM, since UEFI defines efi_guid_t as a struct
of UINT32 + UINT16 + UINT16 + UINT8[8], and so it may use load/
store multiple instructions [requiring 32-bit alignment], e.g.,
on GUID pointers passed as function arguments since UEFI's view
of the type has implicit 32-bit alignment.
Let's sort this out for the next release, and revert the change
for now.
Fixes: 793423cf07e5 ("efi: Align 'efi_guid_t' to 64 bits")
Reported-by: Heinrich Schuchardt <xypron.glpk@xxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Qian Cai <cai@xxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
---
include/linux/efi.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/efi.h b/include/linux/efi.h
index e6480c805932..100ce4a4aff6 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -48,7 +48,7 @@ typedef u16 efi_char16_t; /* UNICODE character */
typedef u64 efi_physical_addr_t;
typedef void *efi_handle_t;
-typedef guid_t efi_guid_t __aligned(8);
+typedef guid_t efi_guid_t;
#define EFI_GUID(a,b,c,d0,d1,d2,d3,d4,d5,d6,d7) \
GUID_INIT(a, b, c, d0, d1, d2, d3, d4, d5, d6, d7)
--
2.19.2
